As the Green Revolution progresses and enters new battlegrounds for change, water conservation and efficient use of energy have become focal points. The demand for clean water continues to rise as human populations increase. In many areas, demand for clean water is expected to exceed supply, creating a need for increased infrastructure and expense of energy to meet the ever-increasing demand. Further, human activity continues to encroach upon and threaten our precarious river delta regions and other wetlands. Thus, the rate of addition of carbon to the atmosphere continues to increase, making the efficient use of energy a higher priority.
Water shortages and drought are chronic problems in many urban and rural areas. Drought is one of the most costly natural disasters. Damages from drought can be enormous, including agricultural losses, the destruction of residential and industrial landscaping and lawns, damage to urban and suburban trees, and the increased occurrence and risk of wildfires. In some areas, drought can buckle residential building foundations and cause structural damage.
A particularly difficult problem is the waste of clean water. Reducing the waste of water that has already been transported and extensively filtered, purified and cleansed of pathogens is an important element of change in bringing a greener practice to residential settings. Moreover, the clean water that is wasted is very often heated clean water, which contributes further to the waste of energy and carbon emissions.
For example, clothes laundering can be about one-quarter of residential water use, and all of this water is typically discarded after the washing operation. Further, residential faucets and showerheads that have too high a flow rate add to the waste of clean water. In the U.S. alone, inefficient washing machines and plumbing may waste hundreds of billions of gallons of clean water per year. The loss of clean water is especially frustrating because it represents energy already expended in purification and transport.
One way to ameliorate the problem of waste is through water conservation measures such as rationing, replacing washing machines and plumbing fixtures with more efficient models, and establishing greener practices such as harvesting rainwater and using landscaping that requires less water.
Another way to save water is to recycle. It is an unfortunate feature of most building construction that the majority of effluent waste water is in the form of grey water that exits directly to the sanitary drainage system. Grey water is defined in the International Plumbing Code as waste discharged from lavatories, bathtubs, showers, clothes washers, and laundry trays, and in the Universal Plumbing Code as being household waste water from bathtubs, showers, bathroom wash basins, clothes washers, and laundry tubs that has not come into contact with toilet waste, but not water from kitchen sinks or dishwashers.
Because about one-third of all water use is for outdoor watering, the use of grey water for this purpose would be a step in the right direction to advance our transformation to a greener environment.
The widespread installation of grey water recycling devices for both residential and industrial use has been limited in part because of the high capital cost for installation. Moreover, water recycling systems can require significant attention for regular maintenance and service.
WO/2007/040394 relates to a device for reusing greywater and a method of siphoning water from a collecting reservoir to a storage tank.
WO/2006/005118 relates to a modular water treatment apparatus having cells arranged in a treatment bed.
US 2005/0205479 relates to a greywater recycling apparatus having a filter that when clogged is manually cleaned by brushing, reconnecting for reverse flow, or by removal.
WO/2004/057119 relates to a greywater recycling system consisting of one or more tanks which is operating automatically and recycles greywater from a washing machine and uses greywater accumulating only within the same household.
Significant problems with recycling of greywater include emergency overflow conditions, backflow of greywater, clogging of the filter used in the greywater recycling system, and storing within the tank of the recycling system the solid waste that is removed from the greywater.
There is a significant need for systems and methods for water recycling, especially automated systems having reduced maintenance and servicing costs, to reclaim and efficiently reuse residential and other waste water. For example, a conventional filter typically requires that either the filter be replaced or serviced frequently, or that the operative flow process be interrupted to clean the filter.
This invention provides devices and methods for water recycling. Among other things, this disclosure provides an apparatus for reclaiming, purifying, and recycling grey water that advantageously requires little or no maintenance and is easy to manufacture and install.